A lighting device such as a lamp is typically installed in a vehicle. A lighting device typically assists a driver by improving the driver's visibility by increasing an illumination intensity around the vehicle, or notifies people outside the vehicle of a current traveling state of the vehicle.
Lighting devices installed in vehicles typically include a head lamp for irradiating beams to the front of the vehicle, and a rear lamp at the rear of the vehicle for indicating a movement direction of the vehicle or indicating whether a brake of the vehicle is actuated.
A lighting device typically forms low beams or high beams so as to ensure a driver's visibility, for example when the vehicle travels at night. Examples of such lighting devices include light emission diodes (LEDs) having high power efficiency and long lifespan, and laser diodes having a long irradiation distance.